I'm helping restore a 1955 pan head that was in a fire. We are in the process or replacing the oil lines that were burned off.
There are 2 vents in the cases. One at the bottom of the motor an one near the oil pump.
Tipically the lower case was vented to the primary on the pan heads, for primary lubrication or to the air filter backing plate on later versions. I'm routing this one to the atmosphere, as the owner is considering a belt primary.
The other vent near the oil pump, I think, is tipically vented to the top of the oil tank. There is an aftermarket oil tank on this bike with no fitting for a vent. Where and how can I vent this line?
Any help will be appreciated.

 

The oil tank vent is the hole in the right case just above the oil pump and to the left I don't remember an oil tank without a vent ? I alway put a uni-filter 3/8 on the vent line that leaves the left case that lubed the prim chain J&P shows this filter as P/N 400-545 I run this filter up above the trany to keep rain away Water will turn the oil to chocolate when riding in the rain on these old motors My 46 knuck and my 52 pan/shovel run enclosed belt drives ( primary ) with this system

 

This tank must have a vent or the possibilty of oil starvation at some point can exist. I would add a fitting if possible and vent to the case as oem did. Could you fab one up for the actual cap itself and flex line the connection? As for the original vent into the primary, there is a screw on the pump to shut the oil for the chain off. Back in the day, if this screw was not adjusted to provide lube the chain got really rust, fast, so oil carry over would not likely be an issue with it.
Ron

 

Thanks for the information.
I also havn't seen an oil tank without a vent previous to this one. I guess the solution will be to fabricate one.

 

Some caps on off brand tanks had the vent in them.

I had a 65 like 20 lifetimes ago...... And NOW I worry about a valve tick on my Twinkie! HAHA.

Good Luck on your project! Sounds like fun.

 

Thanks.
I think I understand the consept of oil tank venting. But what I need to know is what to do with the engine vent, which is near the oil pump. I think it's called the breather valve vent. If there is no vent nipple at the top of the oil tank, where can the breather valve vent line go?

 

Time for another oil tank !